A Chemometrics-driven Strategy for the Bioactivity Evaluation of Complex Multicomponent Systems and the Effective Selection of Bioactivity-predictive Chemical Combinations

Although understanding their chemical composition is vital for accurately predicting the bioactivity of multicomponent drugs, nutraceuticals, and foods, no analytical approach exists to easily predict the bioactivity of multicomponent systems from complex behaviors of multiple coexisting factors. We herein represent a metabolic profiling (MP) strategy for evaluating bioactivity in systems containing various small molecules. Composition profiles of diverse bioactive herbal samples from 21 green tea extract (GTE) panels were obtained by a high-throughput, non-targeted analytical procedure. This employed the matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) technique, using 1,5-diaminonaphthalene (1,5-DAN) as the optical matrix for detecting GTE-derived components. Multivariate statistical analyses revealed differences among the GTEs in their antioxidant activity, oxygen radical absorbance capacity (ORAC). A reliable bioactivity-prediction model was constructed to predict the ORAC of diverse GTEs from their compositional balance. This chemometric procedure allowed the evaluation of GTE bioactivity by multicomponent rather than single-component information. The bioactivity could be easily evaluated by calculating the summed abundance of a few selected components that contributed most to constructing the prediction model. 1,5-DAN-MALDI-MS-MP, using diverse bioactive sample panels, represents a promising strategy for screening bioactivity-predictive multicomponent factors and selecting effective bioactivity-predictive chemical combinations for crude multicomponent systems

Observation of Vertically Ejected Plumes Generated by the Impact of Hollow Projectiles at Various Velocities

Recently, impact experiments in space have been conducted in planetary exploration using hollow or internally structured projectiles. In laboratory experiments using hollow projectiles to investigate the differences in crater and ejecta from the case of solid projectiles, a plume perpendicular to the target surface has been observed, which has not been seen in conventional cratering experiments using solid projectiles. In this study, we conducted crater-formation experiments using hollow resin projectiles to understand the mechanism through which vertical plumes form in the case of hollow projectiles. We examined the generation of a vertical plume as a function of the impact velocity, v _imp . We found that (i) no vertical plume occurs at v _imp < 200 m s ^−1 , (ii) the cases with or without a vertical plume are mixed at 200 < v _imp < 350 m s ^−1 , (iii) no vertical plume occurs at 350 < v _imp < 800 m s ^−1 , and (iv) a vertical plume occurs at 2 < v _imp < 3 km s ^−1 . We qualitatively discussed the generation mechanism of the vertical plume using the results of recovered projectiles. Depending on v _imp , an empty hole in which there is no projectile materials can be opened along the central axis, resulting in the generation of a vertical plume